New York City developer Harry Macklowe and global architecture firm Gensler have proposed a 96-storey office tower in Midtown Manhattan, which could become the city's tallest skyscraper by roof height.

Details of the proposal, named Tower Fifth, were acquired by the New York Times last week when Macklowe submitted the preliminary application to the Department of City Planning.

The developer – who was behind Rafael Viñoly's 432 Park Avenue – has enlisted Gensler to lead the design, while local practice Adamson Associates Architects will serve as the architect of record.

Tower Fifth is intended to be built on a plot along Fifth Avenue, between 51st and 52nd streets.

Designed to reach 1,556 feet (474 metres) tall, it would become the city's tallest skyscraper by roof height. But One World Trade Center, which reaches 1,776 feet (541 metres) to the top of its mast, would still retain the official title.

To build his tower, Macklowe will have to acquire air rights from the surrounding buildings – the majority likely to come from nearby St Patrick's Cathedral.

Renderings of the skyscraper proposal show a glassy, rectangular structure punctured with square windows – almost like a sister to 432 Park Avenue. The exterior will be clad in an "expensive and energy-efficient facade rarely seen in the United States", according to reports.

At the top, the skyscraper would segment into three volumes. The lower block would cantilever out to host "the city's tallest observatory", with access to a corkscrew slide.

This is among a number of features included alongside office space, such as luxury amenities like a pool, a yoga room and a multilevel running track.

Tower Fifth's offices would be elevated above a tall glass lobby, offering views of the cathedral opposite.

Macklowe has already met with New York's Planning Department, the Landmarks Preservation Commission and members of the local community board to discuss the project, according to the New York Times report, to speed up the process of constructing the skyscraper.

The project is likely to cause contention for its proximity to several landmarks and important buildings, such as St Patrick's, Rockefeller Center and John Peirce Mansion. It is also outside the size limits of Midtown zoning.

If approved, Tower Fifth will join a host of new supertalls – measuring between 980 and 2,000 feet (300 and 600 metres) – that are rising or complete in Midtown Manhattan.

These include 432 Park Avenue, Christian de Portzamparc's One57, Adrian Smith + Gordon Gill Architecture's Central Park Tower and Jean Nouvel's 53W53.

Gensler has much experience with skyscrapers – its Shanghai Tower is currently the world's second-tallest building, while other projects include adding a glass skyslide to Canada's tallest skyscraper and a pair of skyscrapers proposed for the Sri Lankan coast.

Renderings are by TMRW, courtesy of Gensler.

Project credits:

Developer: Macklowe Properties
Design architect: Gensler, in collaboration with Harry Macklowe
Architect of record: Adamson Associates Architects